why i cant see my 4 devices, just see 2

i have 4 devices registered in find my iphone

iphone 4s ios 6.0.1

ipad 2 ios 6.0.1

macbook white mountain lion

macbookpro lion

i just cant see 2 of them on "find my iphone", if i turn off one of the visible ones, one of two "offline" devices enter en map as online

why is this happening?

before ios6, mountain lion and new Fxxx maps always see the 4 devices